The present disclosure relates generally to a planetary gear system and more particularly relates to a cooling arrangement of a planetary gear system for use in gearboxes.
Gearboxes are used for power transmission in many systems such as, wind turbines, automobiles, aircraft and locomotives. A gearbox typically includes components such as a housing, shafts, bearings, and gears. Various gearbox designs are available to meet different speed transmission requirements. Of concern herein is an epicyclical gearbox including a planetary gear system, a sun gear and a ring gear.
In typical prior art, the planetary gear system is supplied with sufficient lubricant such as oil to reduce friction and provide wear protection for gear teeth, bearing surfaces, and other contacting surfaces in relative motion. For example, a set of spray bars may be used for supplying lubricant to the sun-to-planet and planet-to-ring meshes of the epicyclical gearbox. The lubricant is also a medium for conducting waste heat away from the planetary gear system.
It is desirable to remove the used lubricant as completely and quickly as possible, otherwise the gears may continually agitate the residual lubricant. Agitation of the residual lubricant degrades the power transmission efficiency of the gear system and elevates the lubricant temperature, making it more difficult to cool the lubricant to render it suitable for repeated use as a heat transfer medium.
Thus, am improved planetary gear system, would be desired in the art. For example, a planetary gear system with improved lubrication and cooling features would be advantageous.